1. Field of the Invention
This invention relates to candle wax compositions containing esters of dicarboxylic acids and which have improved mold and pin release properties.
2. The Prior Art
Today's modern candle bears small resemblance to the old-fashioned variety of yesterday. Yet, despite this, the basic production methods have remained the same. Candles are either molded, dipped or rolled. In the molding process the mold release characteristics of the wax become very important.
The molding of candles represents one of the most mechanized of the candle-making procedure. Typically a candle-molding machine comprises a number of cylindrical metal molds made of tin or lead-tin alloy and oriented vertically. The temperature of the molds can be controlled by circulating hot or cold water. Within each mold there is a plunger which ejects the finished candle after it is molded. At the ends of the plungers are tip formers through which the wick passes up the mold center and which imparts the characteristic shape to the burning end of the molded candle. After the wicks are in place, molten candle wax is poured into the mold. Atop the molds is an overflow space that is filled to allow for contraction of the wax in the mold as it cools, this excess material being cut off after the candle has hardened. The candles are then forced out of the molds by the plungers. Any sticking of the candles to the molds or plungers as they are being removed from the machine will shut down the process while the candles are removed manually, resulting in a significant loss in efficiency. The spiral taper candle is perhaps the most difficult of the molded candles to remove from the mold. The removal action requires enough pressure on the plunger at the bottom of the mold to effect release and to also virtually unscrew the candle from the mold. Sticking of the wax to the mold or plunger must be kept at a minimum.
Votive candles are molded similar to above. The wicks, however, are not cast in place. Rather, there is a metal pin in the center of the molded candle to accommodate the wick in a second operation. The molds are completely filled with melted wax with an excess in a reservoir chamber above each mold. This excess wax above each mold accommodates the shrinkage of the wax down into the molds as the candles are cooled. Upon complete solidification of the wax, the pins in the mold are removed and the excess wax is cut flush and level across the open surface of each mold. The molded candles are then simultaneously ejected from the mold by raising a plunger in each. In the molded candle operation it becomes critical that the candle wax not stick to the die, plunger or pin.